JPH023402Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] This invention relates to an improvement of an automatic retanbend insertion chuck for automatically inserting a retanbend forming a folded portion of a tube such as a fin-tube heat exchanger into a tube.

[Technical background of the invention]

Figure 1 shows a conventional retanbend automatic insertion chuck.
A concave portion 2 is formed by cutting down in a U-shape, and the rear surface 3 is used as a clamping surface. A pair of L-shaped fingers 5, 5 are rotatably attached to the upper part of the front surface of the chuck casing 1 by pins 4, and the lower end of each finger 5 reaches into the recess 2. . Each finger 5 is biased in the direction of contacting the clamping surface 3 by a coil spring 7 (FIG. 3) disposed in a hole 6 formed in the front surface of the chuck casing 1.

A press-fitting head 8 whose lower surface 9 is an arcuate pressing surface and which can be moved up and down is disposed within the recess 2.
This press-fitting head 8 is supported by a pair of left and right support rods 10, 10 passing upward through the chuck casing 1. A return spring 11 is provided between each support rod 10 and the upper surface of the chuck casing 1.
is interposed to urge the press-fit head 8 upward.

According to the above-described configuration, the back curved surface 13 of the return bend 12 is brought into contact with the pressing surface 9 of the press-fitting head 8, and then the return bend 12 is held between the spring-biased fingers 5 and the clamping surfaces 3. After connecting both support rods 10 to an actuator (not shown), both ends of the return bend 12 are connected to the heat exchanger 1.
4, and drive the actuator to lower the press-fitting head 8 against the spring 11 to press-fit both ends of the return bend 12 into the tube 16. .

[Problems with background technology]

By the way, the pressing surface 9 of the press-fitting head 8 is designed to fit the return bend 1 in consideration of the special shape of the return bend 12.
2 into the recess 2 of the chuck casing 1, it has an arcuate surface as described above. Moreover, the curvature of the pressing surface 9 is set to be a larger curvature R than the curvature of the back curved surface 13 of the retan bend 12 in consideration of manufacturing errors of the retan bend 12, so there is a gap between the pressing surface 9 and the back curved surface 13. occurs, and when the return bend 12 is clamped between the finger 5 and the clamping surface 3, the return bend 1
The press-fitting center of the return bend 12 shifts due to the eccentricity a of 2 (Fig. 2), and as shown in Fig. 2, a composite force F of vector b+c acts on the return bend 12 from the press-fitting head 8, and the return bend 12 undergoes posture deformation. wake up

Furthermore, when the return bend 12 is press-fitted into the tube 16, as shown in FIG. This may cause vibrations and cause incorrect insertion of the retanbend 12.

Furthermore, since the pressing surface 9 in the thickness direction of the press-fitting head 8 is flat, as shown in FIG. 4, it is impossible to hold the return bend 12 when the press-fitting is completed, and there is a risk of insertion errors and posture errors.

As described above, the conventional retanbend automatic insertion chuck has a problem in insertability of the retanbend 12.

[Purpose of invention]

The object of this invention is to provide an automatic return-bend insertion chuck that eliminates the drawbacks of the conventional chuck described above and has higher reliability of return-bend insertion than the conventional chuck.

[Summary of the idea]

In order to achieve the above-mentioned object, the retanbend automatic insertion chuck according to the invention includes a chuck casing provided with a clamping surface, and a chuck casing rotatably pivoted to the chuck casing and connected to the clamping surface by the bias of a spring. An automatic return bend insertion chuck having fingers for holding the return bend therebetween, and a press-fitting head that has a pressing surface that comes into contact with the curved back surface of the return bend and moves along the holding surface to insert the return bend into the tube,
The pressing surface of the press-fitting head is formed in a trapezoidal concave shape in the width direction of the press-fitting head and also in a concave shape in the thickness direction, and a protrusion for retracting the finger is provided on the front surface of the press-fitting head. This is what I did.

[Example of idea]

The present invention will be explained below with reference to embodiments shown in the drawings. Note that the same components as those of the conventional device described above are denoted by the same reference numerals in the drawings, and the explanation thereof will be omitted.

A pair of front and rear brackets 14, 14 extending upwardly are projectingly provided on the chuck casing 1, and a support plate 15 is supported at the upper ends of both brackets 14. A midget cylinder 16A is attached to the upper part of this support plate 15, and the piston rod 17 of this cylinder 16A is attached to the support plate 15.
extends below. This piston rod 17 is connected to support rods 10, 10 via a stroke adjustment mechanism 18. Note that this stroke adjustment mechanism 18 is similar to that of the bracket 14.
It can be adjusted via an opening (window) 19 formed in the.

The support plate 15 has a pair of left and right columns 20, 20.
are erected, and a casing 21 is fixed to these supports 20. This casing 21
As shown in detail in FIGS. 6A and 6B, a settling ring 22 with a tapered inner peripheral surface is screwed into the setting ring 22, and the casing 21 is screwed into the settling ring 22.
A lever 24 is provided that projects outside the casing 21 through a circumferential elongated hole 23 . Therefore, by rotating the lever 24, the settling ring 22 undergoes a screw movement. Further, a chuck ring 25 having a slit is disposed so as to be in sliding contact with the tapered inner peripheral surface of the set ring 22, and upward movement of the chuck ring 25 is restrained by the top wall of the casing 21. Further, downward movement of the chuck ring 25 is restrained by a sub-casing 26 screwed into the casing 21.

A support shaft 28 that is vertically attached to the fixing member 27 is inserted into the chuck ring 25, and after inserting the support shaft 28, the lever 24 is inserted into the elongated hole 23 from the state shown in FIG. 6A. When the set ring 22 rotates along the axis, the set ring 22 makes a screw movement, moves the chuck ring 25 inward, and holds the support shaft 28 by the chuck ring 25. Therefore, the return bend automatic insertion chuck is fixed member 2.
7 can be easily and removably attached. In addition,
When the lever 24 is rotated in the opposite direction to that described above,
The support shaft 28 is released from being held by the elastic force caused by the hardening of the chuck ring 25.

On the other hand, the pressing surface 9a of the press-fitting head 8a is formed into a trapezoidal concave shape in the width direction of the press-fitting head 8a, as shown in FIG. The pressing surface 9a of the press-fitting head 8a is formed into a V-shaped concave shape in the thickness direction of the press-fitting head 8a, as shown in FIGS. 8A and 8B. Furthermore, protrusions 29 are provided on the front surface of the press-fit head 8a to correspond to each finger 5 and prevent the fingers 5 from being pressed against the return bend 12 by the spring 7.

According to the above-described configuration, when the return bend 12 is held between the fingers 5, even if the return bend 12 is eccentric by an amount a as shown in FIG.
Since the pressing force G of the return bend 12 by the press-fit head 8a always acts on the return bend 12 in the vertical direction from the horizontal pressing surface 9a of the press-fit head 8a, the attitude of the return bend 12 does not change. Furthermore, when press-fitting the return bend 12 by the press-fitting head 8a, as shown in FIG. can. Furthermore, just before the insertion ends, as shown in FIG. 8B, the protrusion 29 on the front surface of the press-fit head 8a resists the spring 7 and retracts the finger 5, so that the finger 5 does not adversely affect the insertion of the return bend 12. There is no.

According to the embodiment described above, since the support shaft 28 can be held by the wedge action, the chuck can be mounted with high precision, and can be easily attached and detached, and can be attached to various devices, whether robots or special-purpose machines.

Further, the midget cylinder 16A is small and lightweight, and its stroke can be adjusted, and the configuration on the driving side is simple, and position control in the case of robots and the like is highly reliable and can be performed at high speed.

[Effect of idea]

As explained above, in the retanbend automatic insertion chuck according to the present invention, the pressing surface of the press-fitting head is formed in a trapezoidal concave shape in the width direction of the press-fitting head and also in a concave shape in the thickness direction. A protrusion is provided on the front of the head to retract the finger, so it always applies a vertical insertion force to the return bend, stably holds the return bend with two-point centripetal force, and prevents the finger from interfering with the return bend. This makes it possible to increase the reliability of retanbend insertion compared to the conventional method.

[Brief explanation of the drawing]

Fig. 1 is a front view showing a conventional retanbend automatic insertion chuck, Figs. 2, 3 and 4 are explanatory diagrams showing disadvantages of the chuck shown in Fig. 1, respectively, and Fig. 5 is a front view showing a conventional retanbend automatic insertion chuck. A front view showing an embodiment of the return bend automatic insertion chuck, FIG. 6A is an enlarged sectional view of the structure near the casing 21 in FIG. 5, and FIG. 6B shows a state in which the lever in FIG. 6A is rotated. The explanatory diagrams, FIG. 7, and FIGS. 8A and 8B are explanatory diagrams showing the chuck action of FIG. 5, respectively. 1...chuck casing, 2...recess, 3...
...Holding surface, 5...Finger, 7...Spring, 8,8
a...Press-fit head, 9, 9a...Press surface, 10...
...Support rod, 12...Return bend, 16A...
... Midget cylinder, 18 ... Stroke adjustment mechanism, 21 ... Casing, 22 ... Settling, 24 ... Lever, 25 ... Chuck ring,
28...Support shaft, 29...Protrusion.

Claims (1)

[Scope of utility model registration request] a chuck casing having a clamping surface; a finger rotatably pivoted to the chuck casing and clamping the retardant bend between the chuck casing and the clamping surface under the bias of a spring; In an automatic return bend insertion chuck having a pressing surface and a press-fit head that moves along the clamping surface to insert the return bend into the tube, the press-fit surface of the press-fit head has a trapezoidal concave shape in the width direction of the press-fit head. It is formed into a V-shaped concave shape in the thickness direction,
An automatic return-bend insertion chuck, characterized in that the front surface of the press-fitting head is provided with a protrusion for retracting the finger during press-fitting of the return-bend.